Truth Values of Compound Sentences Worksheets

What Are the Truth Values of Open Sentences? You may be familiar with statements or expressions which are definite values; either true or false. But there is third kind of statement which has no definite value, or its value is hard to find; it can be true for someone and false for someone else. For example: Spring is the best season among all. Now this expression might be true for some people but there are people who like the Winter season more, and for them this statement becomes false. There are other types of expressions whose truth value is almost impossible to determine. These Open Sentences require additional information in order to give the true value. For example: x + 5 = 20. These types of sentences have a variable which has to be replaced with a known value. To determine the truth value of these Open Sentences, we have to set a domain from which the value can be selected. We set a domain for the above example as {5, 10, 15, 20}. Now for the value 10 from the set, the statement will become false, but if the variable x is replaced by 15, the truth value of this statement will be true.

Howard Eves

An expert problem solver must be endowed with two incompatible qualities: a restless imagination and a patient pertinacity.